In looking at the new Quads, I'm interested in trying some alternative fin options in my 2010 Quad. What is the maximum size fin a Surfinz box can take?

Ola_H

26th July 2010, 07:01 PM

I wouldn't go much bigger than the 12cm. 13 maybe. In what way would you like the trim the character of the board?

Chesapeake

27th July 2010, 11:09 PM

Ola,

The fin configuration for small waves and general bump and jump conditions work well for me. In underpowered to powered conditions, I've been able to carve some really tight arcs to work on-shore waves. However, I've had a few sessions with shoulder high waves (both side-on and side) in which the drive and speed in the bottom turn, put me out too far in front of the wave to effect a cutback. It is typical of east coast waves to be slow and close-out fast which demands a tight bottom turn in order to enjoy the wave.

To me it feels like the front fins are pushing back too much, keeping me from tightening up the turn. My approach is to balance out the fins somewhat by reducing front fin size and increasing rear fin size.

I'm open to your opinion on the matter.

Thanks,
Mike

w0uter

28th July 2010, 01:28 AM

I just bought the 13 cm front fins haven't tried them yet ? what should I expect ? will the board have the same drive ? will it be easier to make the board slide ?

let's pray for big wind !

Ola_H

28th July 2010, 04:16 AM

Chesapeake: It's indeed a board with a lot of drive and the bigger the board, the more "on it" you have to be in good conditions. But I'd say that you would have a good chance of getting to grips with the drive by getting a pair o 13cm Quad front fins. These are a little bit different than the 16cm fins in shape, so they keep the center of effort at a good spot and also are not as much smaller in area as the size difference might indicate, but the smaller depth still make the whole board softer in its character and downtunes the drive a little bit. Pushing the rear fins further forward int he box might also help since that makes the fin cluster as a whole less powerful. But you're still dealing with a board with a fair bit of drive so and one way of dealing with it in better waves is to get used to it in less good waves and really learn to use it to your advantage. By pushing it in "bad" stuff (which most of us get much more often than the golden stuff) and really try to milk drive and speed out of the wave you will not only have more fun but also be more prepared for the good days. Another thing to work on with the technique (in fast waves) is to try to resist the temptation to "coast" a bit before entering the bottom turn. Often that feels safer, but by instead going into the bottom turn earlier you will set yourself up much better for turning tight since you are already in the turn before you get up to max speed. To do this successfully, it helps if you just at the turn entry put a bit of downward mast foot pressure on to set the front rail of the board. Not only does this work well with this particular board, but it puts you in a good position to handle speed and chop through the turn. So right at the top of the wave when entering your bottom turn, bend you knees a bit and sort of "crouch" forwards and keep your elbows down. These technique tip is something you of course can try even before getting the smaller fins.

Please report back and tell us how things proceed.

Ola_H

28th July 2010, 04:50 AM

w0uter: The board will still be grippy and drivey, but with a sort of softer and more forgiving sensation too it. I'd say that it mostly takes the edge off the powerfull feel of the board and in critical conditions that gives you some extra time and margins of error to sail it effectively. I wouldn't say it get much easier to tail slide it. A little, but you still have a lot of grip once you set it into a proper top turn. It will generally not slide by if hte sailor just pushes sideways. If you want to slide the tail, a more "classic" technique from te good old single fin times works better. Essentially, you'd want to unload the tail and whip it around. If you want to get into the fine print of that, I'd say a kay issue is how you move your shoulders in the turn. For a good carve, you look where you want to turn and then let your shoulders twist off in that direction (hands closer together on the boom helps). If you want to produce a slide you can lock up the upper body by keeping your shoulders more square with the boom (sometimes keeping your rear hand further back helps achieving this). But to make it work you must also keep your weight over the front foot. For sure, a planned and controlled slide is a more difficult move on these Quads than on a twin fin (where sliding a bit is rather the rule than the exception).

racerX

28th July 2010, 06:05 PM

What is the maximum size fin a Surfinz box can take?

I am also curious about this, given my understanding that this board shape started life as a twin. Is the surfinz box strong enough to support a convential twin fin setup, either using future or fcs, or are the boxes in the wrong place.

Ola_H

28th July 2010, 06:47 PM

I dont think the box, not the tabs on the fcs fins are strong enough for a twin setup. And the boxes would not be in a very good place for a twin setup anyway. If you have a board you want to experiment with, the easiest would be to put in a set of slot boxes in the rear and maybe even in the front too while your at it). The problem might be finding the slot boxes. Of course, you could put in US-boxes too, but then you'd add some serious weight and the installation itself is much more work.

racerX

28th July 2010, 07:44 PM

No don't wont to experiment with modifying the board, was just curous if it could work as a twin with the right sort of fins. Thanks

Chesapeake

28th July 2010, 10:19 PM

Ola,

Thank you for your advice. I'll review your post again before my next wave session and report back to you on my experiences.

I am a bit surprised your recommendation to limit the rear fins to 13cm, given that standard FCS fins come in sizes over 15cm (e.g. MR '78 Asymmetric Twin Fins). I realize that windsurfing a board increases the fin pressure over just surfing, but I thought the Surfinz box was chosen for its strength in addition to its weight and adjustability benefits. I can understand if you are trying to being conservative in your answer. Is there any experiences during the Quad development that would shed any light on the situation?

Ola_H

29th July 2010, 02:58 PM

Yeah, maybe I'm a bit conservative and it might be possible to go further. I know of no failures during R&D.

But before experimenting with oversizing the back fins I still think you should try the 13 fronts (maybe with the 12 quad fins (Drake, standard on the Q76) in the rear. Upwind and planing is still more that good with the 13 fins in the front. And by also upsizing the rear fins, you risk stiffening up the board too much.

But of course, if you downsize the front fins even more, to say 11 or below, and fins a good set of fcs fins around 14 you will have a board with a very different character, closer to a twin fin in style and with much less drive. But again, I can not guarantee how the fcs type boxes would hold up for that and I have to check the placement of the fcs boxes to see if it would indeed have a good chance of working.

Chesapeake

13th August 2010, 11:07 PM

Ola,

I'm in need to replace my factory 11cm rear fins as they have started to show fractures, and the Starboard distributor doesn't have any replacement fins. I've looked at FCS and Futures replacements, but I cannot find similar fins that are symmetrical. You've experimented with Maui Ultra Fins. Would you please comment on your recommendations for a pair of their fins? BTW, This would replace fins for an 86 Quad 2010.

Thanks.

Ola_H

14th August 2010, 12:21 AM

Where are you located?

MUF: I tried a set of their elliptical fins in around 10cm in a proto board which was a slightly smaller variant of the Quad 76. But results were somewhere between variable and inconclusive and unfortunately lost one of the fins before getting to try them more (the board in question had US boxes in the rear and I ran a fcs into US adapter which didn't hold up when the board was whashed up on the rocks after a little mishap). I was kind of intrigued but trying some really fast and sleek rear fins, but even the short test I managed suggests going with their most conventional c-wave style might be the best. My guess is that even with that outline, the MUF profile will give you some more power relative the original fcs fins so a 10 or 12 will likely offter some more rear fin power than the respective original fins.

But tell you the truth, I'm a bit doubtful if upgrading the rear fins will be worth the money compared to a cheap set of fcs center fins. I think that 2 FCS M5 style center fins would pretty much equal the standard 12cm fins and M2 or M3 center fins could probably be used instead of the 11cm standard fins.

Chesapeake

14th August 2010, 08:25 AM

Thanks for the advice Ola.

Chesapeake

14th August 2010, 08:55 AM

BTW, I'm in Annapolis.

mikecole

8th September 2010, 11:31 AM

I sure would like a set of 13's for my 2010 quad but I can't find them? Any advice?

Mike

eastman

19th February 2011, 12:12 PM

I just bought a 2010 quad 71. I reviewed this post before it arrived. I looked for some smaller fins and bought 13 cm and 14 cm mini-tuttle fins from Black Project Fins. Sailed the 13 cm fins the other day on a 4.0. in 30-35 knots. I am about 175 lb. Fins worked great. Softened up the ride, and much more control in jibes and in 3-5 foot cross on waves than the stock 16 cm fins.

mikecole

22nd February 2011, 11:01 PM

I too have settled on the 14's from Blackproject in my 81. Those fins have solved all of the odd cavitation issues I had with the board using the factory 16's. I'm still using the factory 12's in the FCS slots.